Arc-lamp electrode.



UNITED STATES PATENT oEEIoE- ISADOR. LAIDOFF, 0F WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF TENNSYIIVANIA.

ABC-LAMP ELEcTaon No Drawing.

To all whom it may concern:

Be it known that I, ISADOR LADorr, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Arc-Lamp Electrodes, of which the following is a specification.

My invention relates to arcing electrodes of the luminescent or luminous type in which most of the light is emitted from the are instead of from the incandescent tip or tips of one or both of the electrodes, as is the case when simple carbon electrodes are used.

My invention refers particularly to the socalled metallic flame electrodes containing titanium, preferably in the form of one or more of its oxids, and some comparatively good conducting metallic materlal which may also be in the form of one or more of its oxids.

It is well known that the titanium compounds found most serviceable for producmg an efficient and white arc produce, at the same time, a very unsteady arc which causes objectionable flickering of the light emitted therefrom. In impregnated carbon electrodes which contain a preponderance of carbon, certain compounds of fluorin are utilized to strengthen the arc and increase its stability. The fluorin compounds usually introduced into electrode compositions for steadying the are are preferably earth-metal titano fluorids, and, under certain conditions, alkali metal titano-fluorids.

However, in metallic flame electrodes which contain a preponderance of metallic material, such as iron, oxids of iron, etc., fluorin compounds are not particularly effective in precluding the flickering of the are. For this purpose, I have invented a metallic flame electrode which will produce a steady and eflicient arc of desirable color value.

Electrodes containing titanium compounds associated with either carbon or magnetite are in common use. Since titanium carbid, even when associated with a fluorin compound, produces a very unsteady arc, I prefer to use titanium oxid which imparts a yellowish-white tinge to the arc. Thls is the characteristic color of titanium oxid whemburning in an electric arc. Again, I prefer titanium oxid be- Specifleation of Letters Patent.

Patented Oct. 15, 1918.

Application filed June 20, 1914. Serial No. 846,861.

cause it is very stable in combination with 11011 oxid which com rises the main metallic constituent of my e ectrode. Iron oxid is a very desirable constituent of my electrode because it increases the conductivity of the electrode. While the high efficiency of my electrode results lar ely from the luminosity a steady light. The material which I find best suited for steadying the are produced by an electrode of the above-mentioned compositionis a uranium compound. The compound of uranium most easily obtained, and one which produces a highly satisfactory electrode is sodium uranate (Na U 0,).

However, uranium oxid, or any other ura nium compounchmay be used to quiet the are.-

In addition to the above constituents, I may add chromium oxid which prolongs the life of the electrode by preventin the too rapid volatilization in the arc of the lightgiving materials of the electrode.

I have made an excellent electrode in accordance with my invention by using the following constituents in the proportions stated: Ferroso-ferric oxid or magnetite, 14: parts; iron, 9 parts; titanium oxid, 17 parts; sodium uranate, .46 parts; chromium oxid 1.25 parts.

While I have given the proportions of the constituents suitable for making an electrode, it will be understood that these proportions may be materially varied without departing from my invention. where the term titanium oxid is used, the mineral ilmenite having the chemical formula(Fe O 3 (Ti 0) m, where a; and 3 indicate variable quantities, may be employed. While I have specified my preference as to sodium uranate for lending stability to the arc, it will be understood that any uranium compounds may be used to quiet the arc.

The are produced by my electrode gives a very steady light which is slightly yellow, as

a result of the uranium compound. The 110 Again, a

combination of the uranium and titanium, therefore, produces an are having a higlplliy satisfactory color value. The luminous e ciency of the arc resulting from my electrode is slightly better than iron-titanium electrodes of the same composition, but which do not contain the uranium compound.

While I have described my invention as particularly applicable to electrodes in which titanium oxid associated with iron is present, it is to be understood that I am not limited to these metallic constituents, and that my invention consists broadly in the addition of uranium material to arcin electrodes for the purpose of steadying t e are.

I claim as my invention:

1. An electrode comprising titanium material mixed with a compound of uranium;

2. An electrode comprlsing titanium oxid mixed with a compound of uranium.

3. An electrode comprising titanium oxid and sodium uranate.

In testimony whereof I have hereunto subscribed my name this 12th day of June, 1914.

ISADOR LADOFF,

Witnesses:

GoLnm E. MCGEE, B. B. Hmns. 

